Nice list of facts. I would point out that although 2.3% absorption looks small, it's actually huge for just a single layer of atoms! So it's true that graphene

Nice list of facts. I would point out that although 2.3% absorption looks small, it's actually huge for just a single layer of atoms! So it's true that graphene is mostly transparent, but it's actually less transparent than almost any other single layer of atoms. That's why the title of your source is "high optical absorption in graphene." :)